Bounding overwatch

About: Bounding overwatch is a research topic. Over the lifetime, 966 publications have been published within this topic receiving 15156 citations.

Reachable Set Bounding for Homogeneous Nonlinear Systems with Delay and Disturbance

Abstract: Reachable set bounding for homogeneous nonlinear systems with delay and disturbance is studied. By the usage of a new method for stability analysis of positive systems, an explicit necessary and sufficient condition is first derived to guarantee that all the states of positive homogeneous time-delay systems with degree converge asymptotically within a specific ball. Furthermore, the main result is extended to a class of nonlinear time variant systems. A numerical example is given to demonstrate the effectiveness of the obtained results.

Disturbance observer based control for dynamically positioned ships with ocean environmental disturbances and actuator saturation

Abstract: The antidisturbance control scheme for the dynamically positioned ships with ocean environmental disturbances and actuator saturation was presented. The ocean environmental disturbances comprises slowly varying disturbances and additional stochastic disturbances. The stochastic disturbance observer was constructed to online estimate the slowly varying disturbances. Based on estimation, a stochastic antidisturbance controller was proposed by combining the disturbance observer‐based control with the stochastic control, where the actuator saturation was dealt with by the polytopic bounding technique. Furthermore, the optimal control allocation method was introduced to distribute control commands into each actuator. Finally, the ship's position and heading are maintained at the desired values and all signals of the closed‐loop system are asymptotically mean‐square bounded. And comparative simulation under different conditions demonstrates the validity and the superiority of the proposed control scheme.

Stochastic Bounding Models for Performance Analysis of Clouds

Abstract: We propose to evaluate the performance of a cloud node (data center) using hysteresis queueing systems and stochastic bound methods. We represent the dynamic behavior of the cloud node by a hysteresis queueing system with forward and backward threshold vectors. The client requests (or jobs) are represented by bulk arrivals entering the buffer, and executed by Virtual Machines (VMs) which are activated and deactivated according to the occupation of the queue, and the threshold sequences. As the system is quite difficult to analyze, we propose to define different bounding systems "less complex" and easier to study. Two approaches are used, one by aggregating the probability distribution of the batch arrivals and another by taking models with the same sequences of forward and backward thresholds. We show the relevance of the proposed bounding systems by presenting some numerical results for the performance measures of a data center.

On Computation Rates for Arithmetic Sum

Abstract: For zero-error function computation over directed acyclic networks, existing upper and lower bounds on the computation capacity are known to be loose. In this work we consider the problem of computing the arithmetic sum over a specific directed acyclic network that is not a tree. We assume the sources to be i.i.d. Bernoulli with parameter $1/2$. Even in this simple setting, we demonstrate that upper bounding the computation rate is quite nontrivial. In particular, it requires us to consider variable length network codes and relate the upper bound to equivalently lower bounding the entropy of descriptions observed by the terminal conditioned on the function value. This lower bound is obtained by further lower bounding the entropy of a so-called \textit{clumpy distribution}. We also demonstrate an achievable scheme that uses variable length network codes and in-network compression.

Computation and Bounding of Folkman Numbers

Abstract: PhD Thesis under the supervision of Professor Nedyalko Nenov.